脱式计算,能简算的要简算3411+337+671147×2.8+52×2.8+2.837.6-4.87-1.1331-[0.5×(6-5.7)+18]9.3÷[24×(1-38)+3.6][(32+83)÷56-73]÷89.-数学
题文
脱式计算,能简算的要简算
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答案
(1)3
=3
=10+3
=13
(2)47×2.8+52×2.8+2.8 =2.8×(47+52+1) =2.8×100 =280; (3)37.6-4.87-1.13 =37.6-(4.87+1.13) =37.6-6 =31.6; (4)31-[0.5×(6-5.7)+18] =31-[0.5×0.3+18] =31-18.15 =12.85; (5)9.3÷[24×(1-
=9.3÷[24×1-24×
=9.3÷18.6 =0.5; (6)[(
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